Today in History for Sept. 11, 2012

■ On Sept. 11, 2001, nearly 3,000 people were killed on America’s worst day of terrorism as 19 terrorists hijacked four passenger jetliners. Two planes smashed into New York’s World Trade Center, causing the twin towers to fall; one plowed into the Pentagon; and the fourth was crashed into a field in western Pennsylvania.

■ In 1777, during the American Revolution, forces under Gen. George Washington were defeated by the British in the Battle of Brandywine.

■ In 1814, an American fleet scored a decisive victory over the British in the Battle of Lake Champlain in the War of 1812.

■ In 1857, the Mountain Meadows Massacre took place in present-day southern Utah as a 120-member Arkansas immigrant party was slaughtered by Mormon militiamen aided by Paiute Indians.

■ In 1862, short-story writer William Sydney Porter, better known as “O. Henry,” was born in Greensboro, N.C.

■ In 1936, Boulder Dam (now Hoover Dam) began operation as President Franklin D. Roosevelt pressed a key in Washington to signal the startup of the dam’s first hydroelectric generator.

■ In 1941, groundbreaking took place for the Pentagon, now headquarters of the U.S. Department of Defense. In a speech that drew accusations of anti-Semitism, Charles A. Lindbergh told an America First rally in Des Moines, Iowa, “the British, the Jewish and the Roosevelt administration” were pushing the U.S. toward war.

■ In 1954, the Miss America pageant made its network TV debut on ABC; Miss California, Lee Meriwether, was crowned the winner.